Why is my iPhone 5s jumping and flickering?

It just seems to take on a life of it's own, without me even touching it.Sometimes, if I'm trying to text the same letter will keep on repeating or the pages on the phone jump about all over the place. Again without my even touching it. Any ideas.

It just seems to take on a life of it's own, without me even touching it.Sometimes, if I'm trying to text the same letter will keep on repeating or the pages on the phone jump about all over the place. Again without my even touching it. Any ideas.

Two questions for you...first, have you loaded any new app? Sometimes a an app might have an issue that affects how the phone acts. If no new apps, have you reset your device by pressing the home button and the power button simultaneously?